← Back to CVE Explorer

CVE-2026-66337

Full vulnerability record from the local CVENow database.

Description

A flaw was found in libsoup. An unsigned integer underflow in the soup_filter_input_stream_read_until() function causes a heap buffer over-read when parsing multipart HTTP responses. A malicious HTTP server can exploit this by sending a crafted multipart response, potentially causing the client application to crash or disclose sensitive heap memory.

Severity
MEDIUM
CVSS score
6.5 (v3.1)
Vulnerability status
Analyzed
Source identifier
Published
2026-07-24 23:16:51.760000
Last modified
2026-11-05 23:16:55.983000
View original CVE JSON
{
  "id": "CVE-2026-66337",
  "sourceIdentifier": "[email protected]",
  "published": "2026-07-24T23:16:51.760",
  "lastModified": "2026-11-05T23:16:55.983",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A flaw was found in libsoup. An unsigned integer underflow in the soup_filter_input_stream_read_until() function causes a heap buffer over-read when parsing multipart HTTP responses. A malicious HTTP server can exploit this by sending a crafted multipart response, potentially causing the client application to crash or disclose sensitive heap memory."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 10",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup3",
          "cpes": [
            "cpe:/a:redhat:enterprise_linux:10"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 6",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup",
          "cpes": [
            "cpe:/o:redhat:rhel_els:6"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 7",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup",
          "cpes": [
            "cpe:/o:redhat:rhel_els:7"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 8",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup",
          "cpes": [
            "cpe:/a:redhat:enterprise_linux:8"
          ]
        },
        {
          "vendor": "Red Hat",
          "product": "Red Hat Enterprise Linux 9",
          "defaultStatus": "affected",
          "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
          "packageName": "libsoup",
          "cpes": [
            "cpe:/a:redhat:enterprise_linux:9"
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "NONE",
          "availabilityImpact": "LOW"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 2.5
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-07-27T16:01:07.951976Z",
          "id": "CVE-2026-66337",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-125"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:gnome:libsoup:-:*:*:*:*:*:*:*",
              "matchCriteriaId": "C5BAC4F4-3ACD-4F4D-920C-F920FD2C5472"
            },
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:*",
              "matchCriteriaId": "2F6AB192-9D7D-4A9A-8995-E53A9DE9EAFC"
            },
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*",
              "matchCriteriaId": "142AD0DD-4CF3-4D74-9442-459CE3347E3A"
            },
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*",
              "matchCriteriaId": "F4CFF558-3C47-480D-A2F0-BABF26042943"
            },
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*",
              "matchCriteriaId": "7F6FB57C-2BC7-487C-96DD-132683AEB35D"
            },
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:o:redhat:enterprise_linux:10.0:*:*:*:*:*:*:*",
              "matchCriteriaId": "D65C2163-CFC2-4ABB-8F4E-CB09CEBD006C"
            }
          ]
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://access.redhat.com/security/cve/CVE-2026-66337",
      "source": "[email protected]",
      "tags": [
        "Vendor Advisory"
      ]
    },
    {
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2506949",
      "source": "[email protected]",
      "tags": [
        "Exploit",
        "Issue Tracking",
        "Vendor Advisory"
      ]
    }
  ]
}